GTI

class gammapy.data.GTI(table)[source]

Bases: object

Good time intervals (GTI) Table.

Data format specification: GTI

Note: at the moment dead-time and live-time is in the EVENTS header … the GTI header just deals with observation times.

Parameters:
table : Table

GTI table

Examples

Load GTIs for a H.E.S.S. event list:

>>> from gammapy.data import GTI
>>> gti = GTI.read('$GAMMAPY_DATA/hess-dl3-dr1//data/hess_dl3_dr1_obs_id_023523.fits.gz')
>>> print(gti)
GTI info:
- Number of GTIs: 1
- Duration: 1687.0 s
- Start: 53343.92234009259 MET
- Start: 2004-12-04T22:08:10.184(TT)
- Stop: 53343.94186555556 MET
- Stop: 2004-12-04T22:36:17.184(TT)

Load GTIs for a Fermi-LAT event list:

>>> gti = GTI.read("$GAMMAPY_DATA/fermi-3fhl-gc/fermi-3fhl-gc-events.fits.gz")
>>> print(gti)
GTI info:
- Number of GTIs: 39042
- Duration: 183139597.9032163 s
- Start: 54682.65603794185 MET
- Start: 2008-08-04T15:44:41.678(TT)
- Stop: 57236.96833546296 MET
- Stop: 2015-08-02T23:14:24.184(TT)

Attributes Summary

time_delta GTI durations in seconds (Quantity).
time_ref Time reference (Time).
time_start GTI start times (Time).
time_stop GTI end times (Time).
time_sum Sum of GTIs in seconds (Quantity).

Methods Summary

copy(self)
read(filename, \*\*kwargs) Read from FITS file.
select_time(self, time_interval) Select and crop GTIs in time interval.
stack(self, other) Stack with another GTI.
union(self) Union of overlapping time intervals.

Attributes Documentation

time_delta

GTI durations in seconds (Quantity).

time_ref

Time reference (Time).

time_start

GTI start times (Time).

time_stop

GTI end times (Time).

time_sum

Sum of GTIs in seconds (Quantity).

Methods Documentation

copy(self)[source]
classmethod read(filename, **kwargs)[source]

Read from FITS file.

Parameters:
filename : pathlib.Path, str

Filename

select_time(self, time_interval)[source]

Select and crop GTIs in time interval.

Parameters:
time_interval : astropy.time.Time

Start and stop time for the selection.

Returns:
gti : GTI

Copy of the GTI table with selection applied.

stack(self, other)[source]

Stack with another GTI.

This simply changes the time reference of the second GTI table and stack the two tables. No logic is applied to the intervals.

Parameters:
other : GTI

GTI to stack to self

Returns:
new_gti : GTI

New GTI

union(self)[source]

Union of overlapping time intervals.

Returns a new GTI object.

Intervals that touch will be merged, e.g. (1, 2) and (2, 3) will result in (1, 3).